diff --git a/command.go b/command.go index 54748fc67..489e0c3c8 100644 --- a/command.go +++ b/command.go @@ -44,6 +44,10 @@ type Group struct { Title string } +// ErrUnknownSubcommand is returned by Command.Execute() when the subcommand was not found. +// Hereto, the ErrorOnUnknownSubcommand flag must be set true. +var ErrUnknownSubcommand = errors.New("subcommand is unknown") + // Command is just that, a command for your application. // E.g. 'go run ...' - 'run' is the command. Cobra requires // you to define the usage and description as part of your command @@ -254,6 +258,17 @@ type Command struct { // SuggestionsMinimumDistance defines minimum levenshtein distance to display suggestions. // Must be > 0. SuggestionsMinimumDistance int + + // ErrorOnUnknownSubcommand controls the behavior of subcommand handling. + // When the flag is set true the behavior of Command.Execute() will change: + // If a sub-subcommand is not found ErrUnknownSubcommand will be returned on calling + // Command.Exec() instead of the old behavior where a nil error was sent. + // If the flag is false (default) the old behavior is performed. + // For this behavior the child subcommand must be nil. + // Example: in root/service/run - there would be an existing subcommand `run` + // in root/service/unknown - there would be an unknown subcommand `unknown` therefore returning an error + // `service` must have a nil Command.Run() function for this. + ErrorOnUnknownSubcommand bool } // Context returns underlying command context. If command was executed @@ -923,9 +938,12 @@ func (c *Command) execute(a []string) (err error) { } if !c.Runnable() { - return flag.ErrHelp + if c.ErrorOnUnknownSubcommand { + return ErrUnknownSubcommand + } else { + return flag.ErrHelp + } } - c.preRun() defer c.postRun() diff --git a/command_test.go b/command_test.go index 9ce7a529b..1012ca4ad 100644 --- a/command_test.go +++ b/command_test.go @@ -17,6 +17,7 @@ package cobra import ( "bytes" "context" + "errors" "fmt" "io" "os" @@ -174,6 +175,94 @@ func TestSubcommandExecuteC(t *testing.T) { } } +func TestSubcommandExecuteMissingSubcommand(t *testing.T) { + rootCmd := &Command{Use: "root", Run: emptyRun} + childCmd := &Command{Use: "child", Run: nil, ErrorOnUnknownSubcommand: false} + child2Cmd := &Command{Use: "child2", Run: emptyRun} + rootCmd.AddCommand(childCmd) + childCmd.AddCommand(child2Cmd) + + // test existing command + c, output, err := executeCommandC(rootCmd, "child") + if !strings.HasPrefix(output, "Usage:") { + t.Errorf("Unexpected output: %v", output) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } + + // test existing sub command + c, output, err = executeCommandC(rootCmd, "child", "child2") + if output != "" { + t.Errorf("Unexpected output: %v", output) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child2" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } + + // now test a command which does not exist, we will get no error, just "Usage:" is printed + c, output, err = executeCommandC(rootCmd, "child", "unknownChild") + if !strings.HasPrefix(output, "Usage:") { + t.Errorf("Expected: 'Usage: ...'\nGot:\n %q\n", output) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } +} + +func TestSubcommandExecuteMissingSubcommandWithErrorOnUnknownSubcommand(t *testing.T) { + rootCmd := &Command{Use: "root", Run: emptyRun} + childCmd := &Command{Use: "child", Run: nil, ErrorOnUnknownSubcommand: true} + child2Cmd := &Command{Use: "child2", Run: emptyRun} + rootCmd.AddCommand(childCmd) + childCmd.AddCommand(child2Cmd) + + // test existing command + c, output, err := executeCommandC(rootCmd, "child") + if !strings.HasPrefix(output, "Error:") { + t.Errorf("Unexpected output: %v", output) + } + if !errors.Is(err, ErrUnknownSubcommand) { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } + + // test existing sub command + c, output, err = executeCommandC(rootCmd, "child", "child2") + if output != "" { + t.Errorf("Unexpected output: %v", output) + } + if err != nil { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child2" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } + + // now test a command which does not exist, we expect an error because of the ErrorOnUnknownSubcommand flag + c, output, err = executeCommandC(rootCmd, "child", "unknownChild") + if !strings.HasPrefix(output, "Error:") { + t.Errorf("Unexpected output: %v", output) + } + if !errors.Is(err, ErrUnknownSubcommand) { + t.Errorf("Unexpected error: %v", err) + } + if c.Name() != "child" { + t.Errorf(`invalid command returned from ExecuteC: expected "child"', got: %q`, c.Name()) + } +} + func TestExecuteContext(t *testing.T) { ctx := context.TODO()